Construction was started on the Porto Cathedral in the12th Century, so it is the same age as Portugal. Its characteristic church-fortress appearance brings to mind its role in the Christian reconquest, which gave origin to the country. The Ibero-American series are an initiative by Portugal, Spain and several Latin American countries. Through minting commemorative collector coins for these series since 1992, the participating countries celebrate themes that demonstrate their common history and culture. The Portuguese Mint and Official Printing Office chose the Porto Cathedral as the motif for a commemorative collector coin due to its historical and artistic richness, making it a symbol of the nation. The coin forms part of the VI Ibero-American series, which this year is dedicated to the theme of "Architecture and Monuments".